Abstract

Gamma-aminobutyric acid (GABA) is an important non-protein amino acid with wide-ranging applications. Currently, GABA can be produced by a variety of methods, including chemical synthesis, plant enrichment, enzymatic methods, and microbial production. Among these methods, microbial production has gained increasing attention to meet the strict requirements of an additive in the fields of food, pharmaceutical, and livestock. In addition, renewable and abundant resources, such as glucose and lignocellulosic biomass can also be used for GABA microbial production under mild and environmentally friendly processing conditions. In this review, the applications, metabolic pathways and physiological functions of GABA in different microorganisms were firstly discussed. A comprehensive overview of the current status of process engineering strategies for enhanced GABA production, including fermentation optimization and whole-cell conversion from different feedstocks by various host strains is also provided. We also presented the state-of-the-art achievements in strain development strategies for industrial lactic acid bacteria (LAB), Corynebacterium glutamicum and Escherichia coli to enhance the performance of GABA bioproduction. In order to use bio-based GABA in the fields of food and pharmaceutical, some Generally Recognized as Safe (GRAS) strains such as LAB and C. glutamicum will be the promising chassis hosts. Toward the end of this review, current challenges and valuable research directions/strategies on the improvements of process and strain engineering for economic microbial production of GABA are also suggested.

摘要

γ-氨基丁酸 (GABA) 是一种重要的非蛋白质氨基酸，具有广泛的应用。目前，GABA 可以通过多种方法生产，包括化学合成、植物富集、酶法和微生物生产。在这些方法中，微生物生产越来越受到关注，以满足食品、制药和牲畜领域对添加剂的严格要求。此外，葡萄糖和木质纤维素生物质等可再生且丰富的资源也可用于在温和环保的加工条件下生产 GABA 微生物。本综述首先讨论了GABA在不同微生物中的应用、代谢途径和生理功能。还提供了用于增强 GABA 生产的工艺工程策略现状的全面概述，包括发酵优化和各种宿主菌株从不同原料进行的全细胞转化。我们还展示了工业乳酸菌 (LAB) 菌株开发策略方面的最新成果，谷氨酸棒状杆菌和大肠杆菌可提高 GABA 生物生产的性能。为了在食品和制药领域使用生物基 GABA，一些公认安全（GRAS）菌株如 LAB 和C. glutamicum将成为有前途的底盘宿主。在这篇综述的结尾，还提出了当前的挑战和有价值的研究方向/策略，以改进 GABA 经济微生物生产的工艺和菌株工程。